The district (excluding the west side of Kashiwazaki) was once part of the now-defunct
Koshi District until the
Heian period when the district was created under the name of Mishima District. Prior to the split, Mishima District covered the cities of
Kashiwazaki (excluding the western part of the city, being the areas of Agewa (Kamiwa), Takaze (Takahane) and Warabino from the former municipality of
Kakizaki) and
Nagaoka (parts of the former towns of
Oguni and
Koshiji), and the village of
Kariwa. When
Santō District split off from
Koshi District during the
Edo period, Mishima was renamed to Kariwa. In 1940, the town of
Kashiwazaki became a city. After
Kashiwazaki merged the surrounding areas, the district continued on to shrink. On April 1, 2005, the town of
Oguni merged into the city of
Nagaoka; and a month later, the towns of
Nishiyama and
Takayanagi merged into the city of
Kashiwazaki. With this merger, Kariwa District has only the village of
Kariwa left.
District Timeline Recent mergers • On April 1, 2005 - The town of
Oguni was merged into the expanded city of
Nagaoka. • On May 1, 2005 - The towns of
Nishiyama and
Takayanagi were merged into the expanded city of
Kashiwazaki. == Notes ==